The present invention relates to a device for monitoring a hydraulic brake system for vehicles, in particular a brake system with anti-skid system, comprising a master brake cylinder for generation of an actuating pressure and a brake valve connectable to a pressure medium source and a reservoir and actuatable by way of a travel simulator.
In hydraulic brake systems of this type, actuation of the brakes is controlled by the brake valve fed with external energy. Direct mechanical actuation of the master brake cylinder only takes place when the external energy supply has failed, in order to prevent a total failure of the brake system. Brake systems of this type are of considerable ease of operation and particularly suitable for an anti-skid system because external energy for effecting the control operations is available. The problem with such brake systems, however, is that errors, such as excessive or too little brake clearance or a leakage of the system, cannot be recognized by the driver due to the distance traveled by the actuating element so that a failure of the brake system can occur without prior warning.
The object of the present invention, therefore, is to create a monitoring device for brake systems of the type initially described which will recognize and indicate fail conditions and errors in the brake system.